Blue Man Group was a good family friendly show.
This was one of the first shows I saw in Vegas some time ago. I recall really enjoying the opening act and some of the featured stunts using power tools, instruments and musical interpretations. The performances overall were quite good.
The show can be a bit abstract. However, I would definitely recommend it as a family friendly show or if you have yet to see a show in Las Vegas and you can snag a really great deal.